"We only send one biologist to the den and take precautions on our scent," wrote a Park Service spokesperson on YouTube. "The purpose is to mark these kittens so that we can learn about them as part of our decade-long study to better understand how urbanization is affecting this very vulnerable population."
National Park Service
One of the biggest threats to the area's mountain lions is genetic in nature: Increasingly isolated by human development, Southern California's cougars have become dangerously inbred.
"Typically, all male mountain lions and half of the females disperse to find their own range," wildlife specialist Seth Riley told The L.A. Times. "Here, they try [but] run into freeways and development - and into adult males - and get killed."
To learn more about the effort to save Southern California's big cats, visit the Santa Monica Mountains Fund here.